Fancy Bird Houses

Advice for a hermit crab owner?
Okay…sure, I’ve had mine for four years now, but I’m wondering if I’m doing anything to harm her.
I keep her in a 20 gallon terrarium, two pools, a crab house, room temp., a holey stick that birds like to climb on (I think it’s a cactus skeleton or something), hermit crab food, various shells, rocks, repti-bark as flooring, and I spray the cage to make it humid sometimes.
I don’t want to buy anything fancy, so don’t go and reccomend some $1,000 equipment that I can make at home or something. Is Blanca (the crab) happy? I’m thinking about getting her some companions.
Your terrarium setup sounds awesome. A little bit of warmth is nice- you can get an under-tank heater for about $20-$40 at any pet store (Don’t use a heat lamp!). Other than that, Blanca would probably REALLY like some crabbie friends.
The Different types of Fancy Show Pigeons